A presidential election runoff in Liberia scheduled for Tuesday will be delayed by the Supreme Court’s investigation into accusations of fraud, the National Elections Commission said on Friday.

The former soccer star George Weah and Vice President Joseph Boakai are competing to succeed President Ellen Johnson Sirleaf, a Nobel Peace Prize laureate whose election in 2005 helped draw a line under 14 years of civil war.

The vote would be Liberia’s first democratic transition of power since 1944, but the Supreme Court this week halted preparations while it examined charges by Charles Brumskine’s Liberty Party, the third-place finisher, that the first round, on Oct. 10, was marred by fraud.

Chief Justice Francis Korkpor said the court would issue its decision on Monday morning, one day before what had been the scheduled date of the runoff election.

“The election will definitely be delayed, but we don’t know for how long,” the elections commission spokesman Henry Flomo said.

Mr. Boakai’s ruling Unity Party has backed the Liberty Party’s allegations and even accused Mrs. Sirleaf, one of its own members, of interfering in the vote by holding private meetings with election magistrates.

Mrs. Sirleaf denied that the meetings were inappropriate. Observers from the European Union and the Carter Center said they saw no major problems with the first round vote.

Addressing the court’s five justices, Mr. Brumskine cited “gross irregularities.” In its complaint last week, the Liberty Party cited the late opening of polls, the absence of crowd control and fraud by elections commission officials.

Lawyers for the elections commission replied that the petitioners did not have any evidence and asked that the court lift its stay so that the commission could organize the second round.

The streets of the capital, Monrovia, remained calm with riot police deployed to protect the Supreme Court building and the elections commission headquarters.

Mr. Weah won the first round with 38.4 percent of the vote to Mr. Boakai’s 28.8 percent. Mr. Brumskine won nearly 10 percent.